A process of manufacturing semiconductor substrates (hereinafter, simply referred to as “substrates”) has conventionally used a substrate processing apparatus that performs various types of processing on a rotating substrate by supplying processing liquids to the substrate. Such a substrate processing apparatus may include a cup part that is disposed around a substrate and for receiving, for example, processing liquids dispersed by centrifugal force from the substrate.
Japanese Patent Application Laid-Open No. 2010-10554 (Document 1) relates to a spin processing apparatus for processing substrates by sequentially supplying a plurality of types of processing liquids to the substrates. The spin processing apparatus includes a cup body around a rotary table that holds a substrate. Between the rotary table and the cup body is a processing-liquid receiver that is moved up and down to switch between passages that are connected to a lower portion of the side surface of the processing liquid receiver. This spin processing apparatus switches the passage for each type of processing liquid received by the processing liquid receiver so that the plurality of types of processing liquids are recovered separately. The atmosphere in the cup body is exhausted through a common exhaust pipe provided in the side surface of the cup body.
A substrate processing apparatus disclosed in Japanese Patent Application Laid-Open No. 2011-204933 (Document 2) includes a cup around a spin chuck inside a treatment chamber. The bottom of the cup has a discharge groove for discharging the atmosphere in the cup, together with processing liquids such as deionized water spinned off from the substrate. Exhaust gas and drainage are guided through the discharge groove to a gas-liquid separator located outside the treatment chamber, and separated exhaust gases are guided to an exhaust switcher. The exhaust switcher switches the destinations to which the exhaust gases flow, among three individual exhaust pipes.
A cup of a substrate processing apparatus disclosed in Japanese Patent Application Laid-Open No. 2002-177856 (Document 3) includes a circular ring-shaped first drain tank located on the outer side of the edge of a substrate, and a circular ring-shaped second drain tank located around the first drain tank. The first drain tank has a drain port and an exhaust port in the bottom, and the top of the exhaust port is covered with a skirt part that is inclined in the circumferential direction. The second drain tank also has a drain port and an exhaust port in the bottom, and the top of the exhaust port is covered with a skirt part that is inclined in the circumferential direction.
Substrate processing apparatuses disclosed in Japanese Patent Application Laid-Open Nos. 2013-207265 (Document 4) and 2013-207266 (Document 5) have a plurality of discharge ports in the side surface of a cup. The discharge ports are opened and closed independently of each other by a switchgear. Each discharge port is connected to a gas-liquid separator and an exhaust device that are not connected to the other discharge ports, and a processing liquid discharged from the gas-liquid separator is guided to a recovery system or a drainage system.
Now, the spin processing apparatus of Document 1 cannot switch the exhaust pipe for exhausting the atmosphere in the cup body, even when the type of processing liquid to be used in the processing of substrates has been changed. The substrate processing apparatus of Document 2 can switch the exhaust pipe depending on, for example, the type of processing liquid, but the size of the substrate processing apparatus may increase because the exhaust switcher is provided outside the treatment chamber. In addition, the plurality of types of processing liquids and the exhaust gas are guided through the common piping to the outside of the treatment chamber and thus may mix with the other processing liquids remaining in, for example, the piping. This may cause undesirable mixing and contact and a reduction in the recovery rate of processing liquids.
In Document 3, the discharge of liquid and gas via the first drainage tank and the discharge of liquid and gas via the second drainage tank are switchable according to, for example, the type of processing liquid, but the size of the substrate processing apparatus may increase because a plurality of drain tanks that correspond to the types of processing liquids need to be provided concentrically outside the substrate. In the substrate processing apparatuses of Documents 4 and 5, each of the plurality of discharge ports of the cup is provided with a switchgear that operates independently of the other discharge ports. This may result in a complexity of the structure related to the switching of the discharge of gas and liquid and control of the structure, as well as an increase in the sizes of the apparatuses.
In the substrate processing apparatuses as described above, when there is demand for adjustment of the flow rate of exhaust gas from the exhaust port, a mechanism for adjusting the flow rate of exhaust gas is provided in the exhaust pipe, separately from the structure for switching the discharge of gas. This may complicate the structures of the apparatuses and increase the sizes of the apparatuses.